For example:

The Flood forced the disobedient angels to dematerialize, and, now separated from Jehovah's holy organization, they became an invisible demonic organization under Satan's domination. (Ephesians 6:12) In order to control mankind, they use spiritism, necromancy, astrology and other occult devices. Although unable to take on human form again, they often possess humans, animals and inanimate things such as fetishes.  The Watchtower 1984 March 15, p. 28-29

Necromancy

Necromancy  refers to divination through alleged communication with the dead.

After Charles Russell the first president of WTS died in 1916 the following was said about him keeping contact with the WTS:

This verse (Revelation 8:3) shows that, though Pastor Russell has passed beyond the veil, he is still managing every feature of the harvest work…We hold that he supervises, by the Lord's arrangement, the work yet to be done.
The Finished Mystery 1917 pp. 144, 256

Hence our dear Pastor, now in glory, is without doubt, manifesting a keen interest in the harvest work, and is permitted by the Lord to exercise some strong influence thereupon.
Watch Tower 1917, November 1 p. 6161 [ WTS's reprints]

No one of the temple company would be so foolish as to conclude that some brother (or brethren) at one time amongst them, and who has died and gone to heaven, is now instructing the saints on earth and directing them as to their work.
Jehovah 1934 p. 191

It is fitting, then, that one of the 24 elders, representing anointed ones already in heaven, should stir John's thinking…(Revelation 7:13, 14a) Yes, that elder could locate the answer and give it to John. This suggests that resurrected ones of the 24-elders group may be involved in the communicating of divine truths today.
Revelation – Its Grand climax At Hand! 1989 p. 125

Charles Russell believed that "A truth presented by Satan himself is just as true as a truth stated by God…Accept truth wherever you find it, no matter what it contradicts." (Zion's Watch Tower 1879 July pp. 8-9) In similar vein the WTS of today also uses any sources at their disposal to confirm their "truth", notwithstanding that Russell's statement is condemned in the Bible! (John 8:44)

Although rejecting spiritism the WTS repeatedly used the writings, of a known spiritist Johannes Greber, as a scholarly support for their beliefs. The WTS was  aware of Greber's spiritistic connections from 1955 but continued to use his works until 1987 (particularly to support their  incorrect translation of John 1:1) while at the same time denying  that they were aware of  Greber's spiritistic practices! (Investigator No. 24, May 1992.) After being exposed for the  use of Greber's works the WTS  apparently stopped  using him.

 WTS has however found another spirit medium in one John S. Thompson to support their John 1:1 translation! He is listed as an authority in the WTS's Kingdom Interlinear Translation 1985 p. 1139-1140. Research in Thompson's book, The Monotessaron, or The Gospel History, According to the Four Evangelists (1829)  shows that his inspiration and direction came from the spirit world!

Demons

The WTS has always had a morbid fascination with the subjects of demons and Jehovah's Witnesses (JW) have developed tremendous fear of demons and Satan. Russell used to write about spirit manifestations. (eg. Zion's Watch Tower 1907 October 1 p. 4069 WTS reprints)

 Recent Watchtower publications also have warnings and instructions on how to deal with demons and demonized objects, shunning  omens and  "voices", rejecting modern "demonized" music, resisting wicked spirits etc. (The Watchtower 1974 June 1 p.328; 1983 October 15 pp. 11-15; 1963 March 15 pp. 186-190)

Jerry Bergman in his book Jehovah's Witnesses and the Problem of Mental Health (1992) relates  case histories showing how the WTS is seriously demon-oriented.

There have been numerous cases where a  JW was perceived by the WTS elders to be demon-possessed. The  elders then frequently take charge of the unfortunate situation and enter the house of the "possessed" JW and systematically start to destroy by burning whatever objects which they think are devil-related! This Shamanistic practice would result in the destruction of  crosses, rosaries, pictures, books, heirlooms and even items like blankets, furniture and clothing if acquired from someone or a body which is considered by the elders to be  in league with Satan!

 Havor Montague in his article The Pessimistic Sect's Influence on Mental Health: The case of Jehovah's Witnesses states that he "has worked with many cases where the suggestion of "demon influence" has been the factor that has caused the neurotic witness to become a complete psychotic." (p. 144)

Astrology

WTS regularly condemns astrology  and  star worship as pagan.
(Awake! 1994 July 8 pp. 3-7)

But, for 62 years (1891-1953) the WTS taught that God resided on star Alcyone, which was the eternal throne of God, and from there he governed the universe. Also the Great Pyramid, of Egypt, which was also considered by the WTS as God's  Stone Witness, provided additional proof of the location  God's throne on the star Alcyone. (Studies in the Scriptures Volume 3 1891 pp. 313-369;  Reconciliation 1928 p. 14) At the WTS's burial lots in near Pittsburgh City a large pyramid  shaped monument is erected near Russell's grave, seven feet high and nine feet across with the Knight Templar logo atop the pyramid.

Astrology and  planetary  positions were used to support the WTS's predictions of the "long promised era" to start by 1914.
(The Watchtower  1903 May 1 p. 3184  WTS reprints)

The three Magis, who came to visit the new born Jesus, are considered by the WTS as pagans because they came "from eastern parts" which was the then centre of occult worship and because they depended on astrology (a  star) to guide them! (The Watchtower 1983 October 15 pp. 11-15)

For more details regarding WTS astrology connection refer Investigator No. 41,  March 1995.
 

WTS and the Freemasons

Fritz Springmeier in his book The Watchtower and the Masons presents a  convincing  insight in WTS's early connection with the occultic Freemasons.

The following are a few of the parallels between the two organizations presented by Springmeier.

· Jehovah is the most important word being the basis of their dogma, and the name of their God.

· Both use the Masonic term "Great Architect"

· Both believe God yielded power to a lesser god.

· Both believe in a future life for all mankind, a new Golden Age.

· Both emphasize continuing revelation.

· Both see an exclusiveness to truth.
 

Communication with Angels

Joseph Rutherford the second president of the WTS believed his spiritual enlightenment came from angels because the Holy Spirit had ceased functioning since 1918. The angels channeled information into his mind from God residing on the star Alcyone. (Preservation 1932 pp.51; 201-203; Watchtower 1931 November 1 p. 327; The Watchtower 1934 April 1 p. 105)

Finally a quote from The Occult (Colin Wilson 1979):

The artist…sees clearly that the 'solution' to the curious pointlessness of most human existence is not another life but  the occasional moments of ecstatic intensity and control when this universe seems infinitely interesting and the idea of eternal life, in this universe, entirely delightful.  This is an idea that can be found in Russian mysticism - in Fedorov, Dostoevsky, Rozanov - that eternal life means life on this earth, not in another world. The Jehovah's Witnesses oddly enough hold a similar doctrine: that after the Day of Judgment, the earth will turn into Paradise. (p. 762)   (Italics in bold added)