The Election Protection Coalition reported receiving 1000 calls about election problems. They note that the calls were all over the board. Here is a key section of the report:

Jonah Goldman, director of the National Campaign for Fair Elections of
the Lawyers’ Committee’s Voting Rights Project, said, “In this historic
primary season, voters across the country have turned out in droves to
exercise their fundamental right to vote. Today Pennsylvanians followed
suit. Unfortunately, the heartening story of record turnout is tempered by
the real problems voters face as they try to cast a ballot. Poorly trained
poll workers, problems with voting machines and inaccurate voter
registration rolls caused countless eligible voters to be needlessly
refused the right to vote.”

The high turnout exposed many of the fundamental problems that plague
the election administration system throughout the state, together with
allegations of voter intimidation and disenfranchisement merit further
investigation. One of the most troubling issues today was a barrage of
reports from voters who have been registered as Democrats for years, but
were listed as unaffiliated and so had to vote provisionally. When this
problem surfaced earlier in the day, the Coalition took action by alerting
the county Boards of Election to the issue and releasing a statement to the
media advising voters who encounter this problem to vote provisionally. It
is unclear at this time how widespread this problem was.

The most frequently reported problems throughout the day included
general polling place issues such as poll workers giving incorrect
information, rule violations and poor administration regarding polling
locations (250+ calls); registration issues (200); equipment malfunction at
the polls (150) and voter intimidation (80+).